Spunk and Moxie is a fun and unique platformer that stars a couple of piles of goo grown in a secret lab by an evil scientist. The scientist was developing a formula to give himself extreme athletic powers and that formula mutated into the gooey duo known as Spunk and Moxie.

The two goos are filled with energy and will bounce endlessly through the level. You can control their jumping, but Spunk and Moxie will zip through each stage on their own, meaning all you can try to do is corral them into the right direction to complete a level.

When you open the app you can choose to play as either character. Spunk is a green goo while Moxie is a pink goo with a bow. Both of them behave in the same way, moving forward on auto pilot. Your job is to tap on the screen to cause them to jump at key points to navigate passage ways, levers, platforms, and obstacles.

You have a limited amount of goo, and running into hooks and spikes throughout the level will drain it, which is a time limit of sorts. There are quite a few one-way platforms that are only accessible when bouncing in a certain direction, which can make some of the levels quite challenging to navigate. The idea is to get to the end pipe to progress to the next stage, while snapping up as many gems as possible.

It can be tough to finish levels because you might often bounce right on by the passageway that you need, before dropping down another tunnel that takes you back to a beginning spot in the level. Expect to spend some time figuring out the ins and outs of each stage before being able to move on.

The app incorporates some special abilities, including a temporary rage potion that allows your character to smash through path-blocking wooden boxes, clearing up previously unusable pathways. You also need to figure out how and when to use these potions, which adds another layer of difficulty to the game.

Spunk and Moxie isn’t the easiest platform game, but the challenge that it presents is what makes it so addictive. I loved the fast pace, which had me coming back to the game time and time again. Watching the gooey characters bounce around the level is a lot of fun too, thanks to the bright, vibrant graphics.

This game has 30 hand-painted levels, along with Game Center integration for achievements. You can even race the ghosts of other players to top leaderboards, which adds an endless amount of gameplay.

What I liked: This game is a throwback to old school platformers. It’s challenging, fun, and occasionally frustrating. It even has hidden keys that will allow you to unlock cameo characters from other indie games like Super Meat Boy and Spelunky.

What I didn’t like:Bouncing past your intended goal time and time again can be annoying, and I did have a few crashes while playing.

To buy or not to buy: If you enjoy challenging platform games, Spunk and Moxie is well worth the purchase price.